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The purpose of this study was to characterize the peels of a CN1 somatic hybrid obtained from two dihaploid potato lines (Cardinal H14 and Nicola H1) in terms of the health‐promoting phenolic compounds (phenolic acids and anthocyanins). The CN1 hybrid is defined by a pink tuber skin color making it different from the light‐yellow‐skinned “Spunta,” which is the most commonly grown potato cultivar in Tunisia. Oven‐dried peel samples derived from CN1 hybrid and cv. Spunta were ground, and phenolic compounds were extracted with water or methanol for quantification. Lyophilized peels were used for the phenolic acid and anthocyanin analyses. Higher total quantities of phenolic compounds were recovered in methanol extracts compared with water extracts. A slightly higher concentration of phenolic acids (100 mg/100 g DW) was obtained in the lyophilized peels extract of CN1 hybrid than in the cv. Spunta corresponding sample (83 mg/100 g DW). The profiles of the chlorogenic acid isomers were almost identical in both of CN1 hybrid and cv. Spunta. Caffeic acid (CA) and three caffeoylquinic acids (CQAs): 3‐CQA, 4‐CQA, and 5‐CQA, were identified from both genotypes, 5‐CQA being the dominant form in both potatoes. Since the CN1 hybrid has a pink skin color, its anthocyanin profile was also determined. The anthocyanin quantity in the CN1 peels was 5.07 mg/100 g DW, involving six different anthocyanins that were identified within the extract, namely, Pelargonidin‐3‐rutinoside‐5‐glucoside, peonidin‐3‐rutinoside‐5‐glucoside, coumaroyl ester of pelargonidin‐3‐rutinoside‐5‐glucoside, coumaroyl ester of peonidin‐3‐rutinoside‐5‐glucoside, feruloyl ester of pelargonidin‐3‐rutinoside‐5‐glucoside, and feruloyl ester of peonidin‐3‐rutinoside‐5‐glucoside. These results suggest that the peel waste of CN1 somatic hybrid can be considered as a promising source of high‐value compounds for food industry.

Phenolic compounds and ascorbic acid are the main antioxidants in potato tubers. Synthesis of these metabolites is affected by biotic and abiotic factors. The aim was to understand how the genetic background, stage of tuber development and weather conditions impact the synthesis of phenolic compounds, ascorbic acid and tuber yield. Therefore, four potato cultivars with purple or yellow tuber flesh were grown at two different latitudes (61.2° N and 64.8° N) in two consecutive years in Finland. The potato tubers were harvested at different stages of tuber development. Purple-fleshed potato cultivars (‘Blue Congo’ and ‘Synkeä Sakari’) showed the highest gene expression levels for anthocyanin biosynthesis. The content of anthocyanins and phenolic acids in the tubers was the highest at around 70 days after planting (DAP) and decreased during tuber development. Temperature was the main weather variable affecting the synthesis of phenolic compounds. The potato trial located at 61.2 °N in 2014 (Kokemäki) was exposed to the highest temperatures and lowest precipitation. This produced tubers with reduced gene expression levels for the synthesis of phenolic compounds and the lowest content of anthocyanins, phenolic acids and ascorbic acid. All the potato tubers from this trial had scabs, which reduced the tuber quality.